From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 55970EB64DD for ; Tue, 11 Jul 2023 20:02:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=SwgZXAIlNdHEXS8jnJwVWJO8de3p2tQuoklFLE0cSzc=; b=etgd7YSLyqBXVi O8ObhU8v98h7kLjUSdkfAZUr97L1FNQpYrAyYdEKyTAV3CENwDI+1FvCDe0EtU7R2nzer9dl7qGXb J11vawaCicoYIFS1MVD1ze+ZqOsxS6TBh09K+WHa+4mmWpS23uN6qJFoksm+MDnDc5gGrEzmdReQv bfcnKbqIj2pbZ05e0Ua5xRxzjqX2zom6h9uVpHtKNXuQf+VcZQLYf2rlQf4CO+9EoMIGie5FUB9ez VQd16ffUMYEM4hRvWq1DMrBA3iRZT2yitOp/8W5oFIk1BnTAmNaPofUObpC9FAZcL/f+6JmHyqyAr cZ+vMVhX7beGu8zxpnJg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qJJYE-00FnII-0t; Tue, 11 Jul 2023 20:01:34 +0000 Received: from out-59.mta1.migadu.com ([2001:41d0:203:375::3b]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qJJY8-00FnEj-1i for linux-arm-kernel@lists.infradead.org; Tue, 11 Jul 2023 20:01:30 +0000 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1689105668; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=H4U0BqZH6IJqZy7LVpNL5UW+eWiw5deb+05/t7QjPmA=; b=Q0IkcWGLQ1D3CsbhY2XMmuHN8nUgph7WOGKfiJcHZLLSN2GvQl5d+kl7obg/EPu+63qFn7 /FscK+P5pCfVMv7GPTnNvPCrofwvE5YolEMldr3Hu2u5MdlwNcNSsPGOyR2QqNmsK4Vs0H bUkMrHzftXJsAQCEeFc2o5jY7GPSI30= From: Oliver Upton To: Marc Zyngier , kvm@vger.kernel.org, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org Cc: Oliver Upton , Kristina Martsenko , seanjc@google.com, Zenghui Yu , isaku.yamahata@intel.com, James Morse , stable@vger.kernek.org, Suzuki K Poulose , pbonzini@redhat.com Subject: Re: [PATCH] KVM: arm64: Disable preemption in kvm_arch_hardware_enable() Date: Tue, 11 Jul 2023 20:00:45 +0000 Message-ID: <168910562680.2605377.17070403411705802542.b4-ty@linux.dev> In-Reply-To: <20230703163548.1498943-1-maz@kernel.org> References: <20230703163548.1498943-1-maz@kernel.org> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230711_130128_733556_2B6FA2A7 X-CRM114-Status: UNSURE ( 8.47 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, 3 Jul 2023 17:35:48 +0100, Marc Zyngier wrote: > Since 0bf50497f03b ("KVM: Drop kvm_count_lock and instead protect > kvm_usage_count with kvm_lock"), hotplugging back a CPU whilst > a guest is running results in a number of ugly splats as most > of this code expects to run with preemption disabled, which isn't > the case anymore. > > While the context is preemptable, it isn't migratable, which should > be enough. But we have plenty of preemptible() checks all over > the place, and our per-CPU accessors also disable preemption. > > [...] Applied to kvmarm/fixes, thanks! [1/1] KVM: arm64: Disable preemption in kvm_arch_hardware_enable() https://git.kernel.org/kvmarm/kvmarm/c/970dee09b230 -- Best, Oliver _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel